CN110220575B - A device for measuring flow coefficient of venturi flowmeter - Google Patents

Abstract

The invention discloses a device for measuring the flow coefficient of a Venturi flowmeter, comprising a timer, a water storage tank, a water supply mechanism and a measuring return mechanism respectively connected at both ends of the water storage tank, and a water supply mechanism and a measuring return mechanism connected between the water supply mechanism and the measuring return mechanism. Diversion mechanism; its measurement effect is good and the accuracy is high. During the whole process of the experiment, the water body can be recycled and used, which can effectively save water resources and reduce water consumption; improve the water body utilization rate and good performance.

Description

A device for measuring flow coefficient of venturi flowmeter

technical field

The invention relates to the technical field of fluid mechanics, in particular to a device for measuring the flow coefficient of a venturi flowmeter.

Background technique

Because the motion law of liquid flow is very complex, all practical problems cannot be solved completely by theoretical research methods. Many unknown fluid motion laws must be explored and discovered through experimental research; the equipment used in the existing Venturi experiment is inconvenient to operate, has poor measurement effect, and has low accuracy of measurement results, and is only suitable for small flow measurement. Low performance.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a device for measuring the flow coefficient of a venturi flowmeter, so as to solve the problems of poor measuring effect and low performance of the existing measuring equipment.

The technical scheme of the present invention to solve the above technical problems is as follows: a device for measuring the flow coefficient of a Venturi flowmeter, comprising a timer, a water storage tank, a water supply mechanism and a measurement return mechanism respectively connected to both ends of the water storage tank, and a water supply mechanism connected to the water supply mechanism The diversion mechanism between the measuring backflow mechanism;

The diversion mechanism includes a first diversion assembly and a second diversion assembly arranged side by side, and both the first diversion assembly and the second diversion assembly include a first test tube communicated with the water supply mechanism, and a first test tube communicated with the water supply mechanism. The second test tube communicated by the measurement backflow mechanism and the venturi tube connected between the first test tube and the second test tube, the venturi tube is connected with a pressure measuring assembly, and the second test tube is connected to the venturi tube. A valve is provided.

Further, the measurement backflow mechanism includes a collecting box arranged on the upper end of the water storage tank, a measuring cylinder located at both ends of the collecting box, a water level stylus assembly located above the collecting box, and a measuring cylinder and a water storage tank. The return pipe between the two, the return pipe is provided with a valve, the bottom end of the water level probe assembly is located in the measuring cylinder, and the end of the second test tube away from the Venturi tube communicates with the measuring cylinder .

Further, the water level stylus assembly includes a bracket arranged above the collecting box, a sleeve arranged on the bracket, a measuring rod arranged in the sleeve, and a stylus connected to the bottom end of the measuring rod. An adjustment knob for controlling the movement of the sleeve is provided at the position where the sleeve is connected, and the end of the stylus away from the measuring rod extends into the measuring cylinder.

Further, the collecting box includes a box body disposed at the upper end of the water storage tank, storage chambers located at both ends of the box body, and a residual liquid collection bin located between the storage chambers at both ends, and the storage chamber is provided with a measuring cylinder, so A drain pipe is arranged between the residual liquid collection bin and the water storage tank.

Further, a drain joint is movably connected to the end of the second test tube away from the venturi tube, and the end of the drain joint is located in the collecting box.

Further, the water supply mechanism includes a box body with an integrated structure, a water supply cavity located in the box body and communicated with the water storage tank, a water storage cavity located at the upper end of the water supply cavity, and a water supply cavity located in the water supply cavity and the water storage tank. The upper water pipe between the cavities is connected with a water pump, and the first and second flow guide components are respectively communicated with the water storage cavity.

Further, a partition is arranged in the water storage cavity, and the water storage cavity is divided into an overflow area and a return area by the partition; a gap is set at the upper end of the partition, and the The overflow area is communicated with the return area, and the return area is communicated with the water supply cavity, and the first flow guide component and the second flow guide component are respectively connected with the overflow area.

Further, the pressure measuring assembly includes a pressure measuring tube connected to the venturi tube and a scale arranged on the outer wall of the box, and the scale and the pressure measuring tube are far away from the end of the venturi tube Correspondingly; the pressure measuring tube includes a first pressure measuring tube and a second pressure measuring tube, the first pressure measuring tube is connected to the throat of the venturi tube, and the second pressure measuring tube is connected to the The neck of the Venturi tube, and the end of the first pressure measuring tube away from the Venturi tube and the end of the second pressure measuring tube away from the Venturi tube are located on both sides of the scale, respectively.

Further, the end of the pressure measuring tube is provided with a screw joint, and the venturi tube is provided with a fixed joint matched with the screw joint.

Further, the water storage tank is provided with a water inlet.

The invention has the following beneficial effects: the device for measuring the flow coefficient of a venturi flowmeter provided by the invention has good measurement effect and high accuracy, and forms a double theoretical flow measurement through the first pressure measuring assembly and the second pressure measuring assembly. system to effectively improve the accuracy of theoretical flow measurement; double actual flow measurement system is formed by measuring two sets of water level probes in the return mechanism, which effectively improves the accuracy of actual flow measurement; and the water storage tank, water supply mechanism, The diversion mechanism and the measuring backflow mechanism form a self-circulating water flow system. During the whole process of the experiment, the water body can be recycled and used, which can effectively save water resources and reduce water consumption; the joints between the pressure measuring tube and the venturi tube are matched and connected. , to ensure the reliable and stable performance of the connection between the two; and through the drain joint at the end of the second test tube, the user can turn the drain joint as required, so as to control the water body to be discharged into the measuring cylinder or the residual liquid collection bin, thereby Improve the accurate control of the inflow of the water body, and after the test is completed, the drain joint is aligned with the residual liquid collection bin, so that the remaining water body in the test tube can flow into the water storage tank along the residual liquid collection bin after the test, improving the water body utilization rate. High performance.

Description of drawings

Fig. 1 is the structural representation of the present invention;

FIG. 2 is a schematic structural diagram of the first air guide assembly or the second air guide assembly in the present invention;

Fig. 3 is the water level probe assembly in the present invention;

4 is a schematic diagram of a header box in the present invention;

5 is a schematic structural diagram of a water supply mechanism in the present invention;

Fig. 6 is the enlarged schematic diagram at A place in Fig. 2;

The reference numerals shown in Fig. 1 to Fig. 6 are respectively indicated as: 1-water storage tank, 2-water supply mechanism, 3-measurement return mechanism, 4-flow guide mechanism, 40-first guide assembly, 41-second guide Flow assembly, 401-first test tube, 402-second test tube, 403-venturi tube, 5-pressure measuring assembly, 404-valve, 30-manifold box, 31-grading cylinder, 32-water level stylus assembly, 33- Return pipe, 320- Bracket, 321- Sleeve, 322- Measuring rod, 323- Stylus, 324- Adjusting knob, 301- Box body, 302- Storage cavity, 303- Residual liquid collection bin, 304- Drain pipe , 20-box, 21-water supply cavity, 22-water storage cavity, 23-upper water pipe, 220-partition, 221-overflow area, 222-return area, 223-notch, 51-scale, 501-section One pressure measuring tube, 502-second pressure measuring tube, 503-screw joint, 504-fixed joint, 10-water inlet.

Detailed ways

The principles and features of the present invention will be described below with reference to the accompanying drawings. The examples are only used to explain the present invention, but not to limit the scope of the present invention.

As shown in Figures 1 to 2, a device for measuring the flow coefficient of a Venturi flowmeter includes a timer, a water storage tank 1, a water supply mechanism 2 and a measurement return mechanism 3 connected to both ends of the water storage tank 1, and a water supply mechanism connected to the water supply mechanism. 2 and the flow guide mechanism 4 between the measurement return mechanism 3. The timer uses a stopwatch to record the water intake time. The water storage tank 1 is the source of the experimental water body, and the water storage tank 1, the water supply mechanism 2, the diversion mechanism 4 and the measurement return mechanism 3 form a self-circulating water flow system. The experimental water body circulates and is reused, saving water resources and reducing waste. The water body in the water supply mechanism 2 is sent to the measurement return mechanism 3 through the diversion mechanism 4, and the theoretical flow rate is measured. The actual flow rate is accurately measured by measuring the return flow mechanism 3 and the pressure measuring component 5, and the Venturi coefficient is measured and calculated by the accurate measurement of the actual flow rate of the theoretical flowmeter.

The diversion mechanism 4 includes a first diversion assembly 40 and a second diversion assembly 41 arranged side by side. The second test tube 402 connected to the measurement return mechanism 3 and the venturi tube 403 connected between the first test tube 401 and the second test tube 402, the venturi tube 403 is connected with the pressure measuring assembly 5, and the second test tube 402 A valve 404 is provided thereon. Two sets of measurement systems are formed by the first guide assembly 40 and the second guide assembly 41 to improve the accuracy of theoretical flow measurement. The water in the water storage tank 1 flows through the first test tube 401 and the Venturi through the water supply mechanism 2 in turn The tube 403 , the second test tube 402 and the measurement return mechanism 3 are finally returned to the water storage tank 1 . The pressure measuring assembly 5 includes a pressure measuring tube connected to the venturi tube 403 and a scale 51 corresponding to the end of the pressure measuring tube away from the venturi tube 403, and the scale 51 is arranged on the outer wall of the box body 20; The pressure measuring tube includes a first pressure measuring tube 1 and a second pressure measuring tube 2, the first pressure measuring tube 1 is connected to the throat of the venturi tube 403, and the second pressure measuring tube 2 is connected to the neck of the venturi tube 403, And the end of the first pressure measuring tube 1 away from the venturi tube 403 and the end of the second pressure measuring tube 2 away from the venturi tube 403 are located on both sides of the scale 51 respectively. Through the scale 51, the height of the water body in the pressure measuring tube can be measured in real time, so as to measure the theoretical flow rate, which is convenient and reliable, and easy to observe.

The measurement return mechanism 3 includes a collecting box 30 arranged on the upper end of the water storage tank 1 , a measuring cylinder 31 respectively located at both ends of the collecting box 30 , a water level stylus assembly 32 located above the collecting box 30 , and a measuring cylinder 31 and the water storage tank 1 . A valve 404 is provided on the return pipe 33, the bottom end of the water level probe assembly 32 is located in the graduated cylinder 31, and the end of the second test tube 402 away from the venturi 403 communicates with the graduated cylinder 31. The water level stylus 323 is the main instrument for experimentally measuring the basic quantity of water level and water surface curve. The water flowing out through the diversion mechanism 4 enters the measuring cylinder 31 for storage, and cooperates with the water level stylus assembly 32 to measure and read the liquid level of the water body in the measuring cylinder 31 . The valve 404 adopts a flow control valve, which can control the flow rate of the water flowing into the measuring cylinder 31. During use, the flow control valve is used to control different flows of the water body to form multiple sets of data under different flow conditions, which is helpful to improve the flow rate. the accuracy of the determination. The used water body flows back into the water storage tank 1 through the return pipe 33, so that the water body can be recycled. During the experiment, first measure the liquid level of the water body in the measuring cylinder 31 before the water body flows into the measuring cylinder 31 through the water level probe 323 as the initial liquid level height. When the liquid level of the water body in 31 is stable, measure the final liquid level height of the water body liquid level in the graduated cylinder 31 by the water level probe 323, and calculate the actual flow rate by the difference between the final liquid level height and the initial liquid level height. . When measuring the fluctuating water level, the highest and lowest water levels in the graduated cylinder 31 should be measured, and the average value should be taken as the average water level.

In order to improve the use performance of the water level probe 323, as shown in FIG. 3, in the present invention, the water level probe assembly 32 includes a bracket 320 arranged above the collecting box 30, a sleeve 321 arranged on the bracket 320, The measuring rod 322 in the sleeve 321 and the measuring needle 323 connected to the bottom end of the measuring rod 322 are provided with an adjusting knob 324 for controlling the movement of the sleeve 321 at the position where the bracket 320 meets the sleeve 321, and the measuring needle 323 is far away from the The end of the measuring rod 322 extends into the measuring cylinder 31 . The bracket 320 is an integral support structure of the water level probe assembly 32, the sleeve 321 is installed on the bracket 320, the measuring rod 322 is embedded in the sleeve 321 through the spring sheet, and drives the sleeve 321 to move up and down through the toothed disk inside. Adjust the up and down movement of the stylus 323, the measuring rod 322 is marked with a scale line, and the reading of the water level can be realized through the scale line. When measuring, hold the measuring rod 322 so that the bottom end of the measuring rod 322 is gradually tipped from top to bottom. Approaching the water surface (do not lift it from the water), until the needle tip just touches the water surface, the height of the water level can be read, and the actual flow rate can be measured.

In order to improve the collection effect of the water body during the experiment, as shown in FIG. 4 , in the present invention, the collecting box 30 includes a box body 301 arranged at the upper end of the water storage tank 1 , storage cavities 302 located at both ends of the box body 301 , and two The residual liquid collection bin 303 between the storage chambers 302 at the end is provided with a measuring cylinder 31 inside the storage chamber 302 , and a drain pipe 304 is arranged between the residual liquid collection bin 303 and the water storage tank 1 . The measuring cylinder 31 is made of a transparent material, and can be a plastic material or a glass material. The storage cavity 302 improves the reliable support and fixation of the measuring cylinder 31, and improves the stability of the measuring cylinder 31 during the experiment; when it is not necessary to supply water into the measuring cylinder 31, the end of the second test tube 402 is extended to the residual liquid collection bin 303, The residual water body is dripped into the residual liquid collection bin 303 and discharged back into the water storage tank 1 through the drain pipe 304 to improve the water body utilization rate and avoid the inaccurate measurement caused by the residual water body dripping into the graduated cylinder 31 .

In order to facilitate the quick switching of the flow direction of the water body between the residual liquid collection bin 303 and the measuring cylinder 31, in the present invention, the end of the second test tube 402 away from the venturi tube 403 is movably connected with a drain joint 405, and the end of the drain joint 405 is movably connected Located in the header box 30 . The drain joint 405 is flexibly connected, and the user turns the drain joint 405 to the top of the measuring cylinder 31 or the top of the residual liquid collection bin 303 according to the needs of use, so as to realize the rapid switching of the flow direction of the water body.

In order to improve the use performance of the water supply mechanism 2, as shown in FIG. 5, in the present invention, the water supply mechanism 2 includes a box body 20 with an integrated structure, a water supply cavity 21 located in the box body 20 and communicated with the water storage tank 1, The water storage cavity 22 at the upper end of the cavity 21 and the upper water pipe 23 located between the water supply cavity 21 and the water storage cavity 22. The upper water pipe 23 is connected with a water pump. The cavity 22 communicates with each other. The water pump is located in the water supply chamber 21, and the water body in the water storage tank 1 is lifted to the water storage chamber 22 through the upper water pipe 23 by the pump.

In order to improve the water circulation effect in the water supply mechanism 2, in the present invention, the water storage cavity 22 is provided with a partition 220, and the partition 220 divides the water storage cavity 22 into an overflow area 221 and a return area 222; the partition 220 The upper end is provided with a gap 223, and through the gap 223, the overflow area 221 and the return area 222 are communicated, and the return area 222 is communicated with the water supply cavity 21, and the first guide component 40 and the second guide component 41 are respectively connected with the overflow area. 221 Connected. When the water body in the overflow area 221 reaches the position of the gap 223, the excess water body flows through the gap 223 to the return area 222, and the return area 222 communicates with the water supply cavity 21, and then flows into the water supply cavity 21 and returns to the water storage tank 1, forming a The water circulation system in the water supply mechanism 2 improves the utilization rate of the water body. In order to facilitate observation, the side of the overflow area 221 facing the first diversion component 40 or the second diversion component 41 is made of transparent material, so that the capacity of the water body in the overflow area 221 can be observed in real time, and the usability of the device can be improved.

In order to improve the reliability of the connection between the pressure measuring tube and the venturi tube 403, as shown in FIG. 6, in the present invention, the end of the pressure measuring tube is provided with a screw joint 503, and the venturi tube 403 is provided with a screw The fixed joint 504 with which the joint 503 mates. The inner wall of the screw joint 503 is provided with an inner thread, and the outer wall of the fixed joint 504 is provided with an outer thread, and the outer thread is matched with the inner thread, so as to realize the threaded connection between the screw joint 503 and the fixed joint 504, and the connection has self-locking performance, which improves the connection. stable reliability and avoid loosening. And the connection is simple and the operation is convenient.

In order to facilitate replenishment of water in the water storage tank 1 , in the present invention, the water storage tank 1 is provided with a water inlet 10 . The water body in the water storage tank 1 is supplemented by the external water source of the water inlet 10, so as to form an external water supply, so that the device itself can realize both internal circulating water and auxiliary water supply by external water source, and the use performance is high.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection of the present invention. within the range.

Claims (6)

1. A device for measuring the flow coefficient of a Venturi flowmeter is characterized by comprising a timer, a water storage tank (1), a water supply mechanism (2) and a measuring backflow mechanism (3) which are respectively communicated with two ends of the water storage tank (1), and a flow guide mechanism (4) connected between the water supply mechanism (2) and the measuring backflow mechanism (3);

the flow guide mechanism (4) comprises a first flow guide assembly (40) and a second flow guide assembly (41) which are arranged side by side, the first flow guide assembly (40) and the second flow guide assembly (41) respectively comprise a first test pipe (401) communicated with the water supply mechanism (2), a second test pipe (402) communicated with the measurement backflow mechanism (3) and a Venturi pipe (403) connected between the first test pipe (401) and the second test pipe (402), a pressure measuring assembly (5) is connected to the Venturi pipe (403), and a valve (404) is arranged on the second test pipe (402);

the measuring backflow mechanism (3) comprises a flow collecting box (30) arranged at the upper end of the water storage tank (1), measuring cylinders (31) respectively positioned at two ends of the flow collecting box (30), a water level measuring needle assembly (32) positioned above the flow collecting box (30) and a backflow pipe (33) arranged between the measuring cylinders (31) and the water storage tank (1), a valve (404) is arranged on the backflow pipe (33), the bottom end of the water level measuring needle assembly (32) is positioned in the measuring cylinders (31), and the end part, far away from the Venturi tube (403), of the second test pipe (402) is communicated with the measuring cylinders (31);

the water level measuring needle assembly (32) comprises a support (320) arranged above the flow collecting box (30), a sleeve (321) arranged on the support (320), a measuring rod (322) arranged in the sleeve (321) in a matching mode and a measuring needle (323) connected to the bottom end of the measuring rod (322), an adjusting knob (324) used for controlling the sleeve (321) to move is arranged at the position where the support (320) is connected with the sleeve (321), and the end portion, far away from the measuring rod (322), of the measuring needle (323) extends into the measuring cylinder (31);

the water supply mechanism (2) comprises a box body (20) in an integrated structure, a water supply cavity (21) which is positioned in the box body (20) and communicated with the water storage tank (1), a water storage cavity (22) which is positioned at the upper end of the water supply cavity (21), and a water supply pipe (23) which is positioned between the water supply cavity (21) and the water storage cavity (22), wherein a water pump is connected to the water supply pipe (23), and the first flow guide assembly (40) and the second flow guide assembly (41) are respectively communicated with the water storage cavity (22);

the pressure measuring assembly (5) comprises a pressure measuring pipe connected to the Venturi tube (403) and a graduated scale (51) arranged on the outer wall of the box body (20), and the graduated scale (51) corresponds to the end part, far away from the Venturi tube (403), of the pressure measuring pipe; the pressure-measuring pipe comprises a first pressure-measuring pipe (501) and a second pressure-measuring pipe (502), the first pressure-measuring pipe (501) is connected to the throat part of the Venturi pipe (403), the second pressure-measuring pipe (502) is connected to the neck part of the Venturi pipe (403), and the end part of the Venturi pipe (403) and the end part of the second pressure-measuring pipe (502) far away from the first pressure-measuring pipe (501) are respectively located on two sides of the graduated scale (51).

2. The device for measuring the flow coefficient of the venturi flowmeter according to claim 1, wherein the collecting box (30) comprises a box body (301) arranged at the upper end of the water storage tank (1), storage cavities (302) respectively arranged at two ends of the box body (301), and a residual liquid collecting bin (303) arranged between the storage cavities (302) arranged at the two ends, a measuring cylinder (31) is arranged in each storage cavity (302), and a drain pipe (304) is arranged between each residual liquid collecting bin (303) and the water storage tank (1).

3. A device for measuring the flow coefficient of a venturi meter according to any one of claims 1 to 2, characterized in that the end of the second test tube (402) far from the venturi tube (403) is movably connected with a drain connector (405), and the end of the drain connector (405) is located in the header box (30).

4. The device for measuring the flow coefficient of the venturi flowmeter according to claim 1, wherein a partition plate (220) is arranged in the water storage cavity (22), and the water storage cavity (22) is divided into an overflow area (221) and a reflux area (222) by the partition plate (220); the upper end of the partition plate (220) is provided with a notch (223), so that the notch (223) communicates the overflow area (221) with the backflow area (222), the backflow area (222) is communicated with the water supply cavity (21), and the first flow guide assembly (40) and the second flow guide assembly (41) are communicated with the overflow area (221) respectively.

5. A device for measuring the flow coefficient of a Venturi flowmeter according to claim 4, characterized in that the end of the pressure measuring pipe is provided with a screw joint (503), and the Venturi pipe (403) is provided with a fixed joint (504) matched with the screw joint (503).

6. A device for measuring the flow coefficient of a Venturi flowmeter according to claim 5, characterized in that the water storage tank (1) is provided with a water inlet (10).

Images